The 'why' absolutely matters - frequently, there are tradeoffs to be made in an implementation; if you don't understand "why" something is being done than it's difficult-to-impossible to evaluate which tradeoff is going to work.
In this particular case, the tradeoffs appear (based on the SO answers) to mostly revolve around how much text the technique is applied to and what the intended uses of that text are (doe selection work, does wrapping work, does accessibility work).
The 'why' absolutely matters - frequently, there are tradeoffs to be made in an implementation; if you don't understand "why" something is being done than it's difficult-to-impossible to evaluate which tradeoff is going to work.
In this particular case, the tradeoffs appear (based on the SO answers) to mostly revolve around how much text the technique is applied to and what the intended uses of that text are (doe selection work, does wrapping work, does accessibility work).